Operating Modes; Direction Of Rotation - Grundfos SL1 Manual De Instrucciones

10.2 Operating modes

The pumps are designed for intermittent operation (S3).
When completely submerged, the pumps can also operate
continuously (S1).
S3, intermittent operation:
Operating mode S3 means that within 10 minutes the pump must
be in operation for 4 minutes and stopped for 6 minutes.
See fig. 15.
In this operating mode, the pump is partly submerged in the
pumped liquid, i.e. the liquid level reaches at minimum the top of
the cable entry on the stator housing. See fig. 2.
P
Operation
4 min.
Stop
Fig. 15 S3, intermittent operation
S1, continuous operation:
In this operating mode, the pump can operate continuously
without being stopped for cooling. See fig. 16. Being completely
submerged, the pump is sufficiently cooled by the surrounding
liquid. See fig. 2.
P
Operation
Stop
Fig. 16 S1, continuous operation
Min. 4" (10 cm)
Fig. 17 Start and stop levels
Make sure that the effective volume of the tank does not become
so low that the number of starts per hour exceeds the maximum
permissible number.
6 min.
t
10 min.
t
Alarm
Start
Stop S1 operation
Stop S3 operation

10.3 Direction of rotation

The pump may be started for a very short period
Note
Note
without being submerged to check the direction
of rotation.
Check the direction of rotation before starting up the pump.
An arrow on the stator housing indicates the correct direction of
rotation. Correct direction of rotation is clockwise when viewed
from above.
Checking the direction of rotation
The direction of rotation should be checked in the following way
every time the pump is connected to a new installation.
Procedure
1. Let the pump hang from a lifting device, e.g. the hoist used for
lowering the pump into the tank.
2. Start and stop the pump while observing the movement (jerk)
of the pump. If connected correctly, the pump will rotate
clockwise, i.e. it will jerk counter-clockwise. See fig. 18.
3. If the direction of rotation is wrong, interchange any two of the
phases in the power supply cable. See fig. 6,
Fig. 18 Jerk direction
7 or 8, 9.
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